I was wondering where to start to set my carbs to the right settings. It is a 2001 Yamaha superjet with 2 bn38 carbs stock settings. I have just recently bought the RIVA racing rpm kit for the ski (Factory B pipe exhaust, flame arrestor w/ 38mm air filter, ADA head, ADA domes, MSD enhancer, Carbon tech low tension reeds, ride plate, impeller). I also am planning on boring out the cylinders to 83mm. What would be a good starting point to set my carbs? Do I need different needle, valves, and spring not sure where to start?
What to set my carb settings too?
- Thread starter The_Ders
- Start date
- Location
- Charlotte, NC
Boring shouldn't really affect the jetting neither will the head. The factory pipe instructions should tell you the recommended jetting
Mike W
Infidel
- Location
- North Florida
john zigler
Vendor Account
- Location
- wisconsin
I see you are in MN. Your Climate, elevation, etc would be very similar to me here in WI.
Personally I have never had luck with Factory pipes jetting recommendations. For one, they always run stock flame arrestors, which is fine, but that will change pop off requirements.
It is Sunday, and I am not in the shop. I keep notes on what has worked for us here in the past. (And we build MANY Super Jets.)
I sell jetting kits, $40 per carb. This includes one pilot jet, main jet, needle and seat, and needle arm spring. $40 /per carb.
If you have not done so recently I usually recommend rebuilding your carbs as well. Clean thoroughly, and install new genuine kits.
https://www.watcon.com/fuel-system/carburetor-jets/jetting-kit
Personally I have never had luck with Factory pipes jetting recommendations. For one, they always run stock flame arrestors, which is fine, but that will change pop off requirements.
It is Sunday, and I am not in the shop. I keep notes on what has worked for us here in the past. (And we build MANY Super Jets.)
I sell jetting kits, $40 per carb. This includes one pilot jet, main jet, needle and seat, and needle arm spring. $40 /per carb.
If you have not done so recently I usually recommend rebuilding your carbs as well. Clean thoroughly, and install new genuine kits.
https://www.watcon.com/fuel-system/carburetor-jets/jetting-kit
Awesome I’ll get a couple of those kits on your site. Do the kits come with the specific size jets and needle/seat/spring I would need and I just have to specify what upgrades I have?
- Location
- Charlotte, NC
I'm running a full 62t engine with a c4 chamber bpipe and dual 38s. I believe I'm at 75 pilot, 135 main, 1.5 n/s 115g spring. Stock flame arrestor with 2 screens removed. Around 1 turn out on top and bottom screws
john zigler
Vendor Account
- Location
- wisconsin
Yes. If you order from my site, please give me all the specs on your build. PIpe, head, carbs, flame arrestor, impeller, and your elevation.
Thank you for the support.